I used this tutorial, in the crockpot.
It made wonderful soap, but I did need to add about double the water it called for to dilute it.
It took 3.5 hours cooking and stirring every 30 minutes. Then, I added water (very hot) right into the crock pot- stirred a bit, put the lid on it and left it overnight (crockpot turned off). In the morning I had to use my stick blender to break up some chunks, and then added the same amount of water again (pretty much filling the crock pot). Turned it on high, took another several hours to dilute.
This is a great thing to do on a Friday night when you have Saturday free to deal with it. I can tell you, it's worth the time. It makes a TON of soap. I love it, and will be making it again.
Go for it!